Carbon nanostructure preblends and their applications

Abstract

A method for preparing a “preblend” of nanostructured carbon, such as nanotubes, fullerenes, or graphene, and a particulate solid, such as polymer beads, carbon black, graphitic particles or glassy carbon involving wet-mixing and followed by optional drying to remove the liquid medium. The preblend may be in the form of a core-shell powder material with the nanostructured carbon as the shell on the particulate solid core. The preblend may provide particularly improved dispersion of single-walled nanotubes in ethylene-α-olefin elastomer compositions, resulting in improved reinforcement from the nanotubes. The improved elastomer compositions may show simultaneous improvement in both modulus and in elongation at break. The elastomer compositions may be formed into useful rubber articles.

What is claimed is: 
     
       1. A preblend composition comprising carbon nanostructures and a particulate solid, said preblend composition prepared by wet-mixing said carbon nanostructures and said particulate solid in a liquid medium, wherein the preblend composition comprises solid core particles of said particulate solid coated with a shell of said carbon nanostructures forming a core-shell material;
 wherein the core particles comprise carbon-based particles selected from the group consisting of graphitic carbon and glassy carbon; and 
 wherein the core particles are regular or irregular in shape and have a size in the range of 20 nm to 20 μm in terms of average longest dimension. 
 
     
     
       2. A preblend composition comprising carbon nanostructures and a particulate solid, said preblend composition prepared by wet-mixing said carbon nanostructures and said particulate solid in a liquid medium, wherein the preblend composition comprises solid core particles of said particulate solid coated with a shell of said carbon nanostructures forming a core-shell material;
 wherein the core particles comprise carbon-based particles selected from the group consisting of graphitic carbon and glassy carbon; and 
 wherein the carbon nanostructures consist of one or more from the group consisting of fullerenes, single-walled carbon nanotubes, multi-walled carbon nanotubes, and their chemical derivatives. 
 
     
     
       3. The preblend composition of  claim 1  wherein the shell coating on the core particles cover a surface area in the range of 50-100% of the total surface area of the core particles. 
     
     
       4. The preblend composition of  claim 1  wherein said preblend composition is further prepared by drying after said wet-mixing. 
     
     
       5. The preblend composition of  claim 1  wherein the preblend further comprises a nanotube network with carbon black particles dispersed therein. 
     
     
       6. A material composition comprising the preblend composition of  claim 1 , wherein said material composition is a polymer composition, an electrolyte medium, a paint, a coating, or a slurry. 
     
     
       7. An article comprising the preblend composition of  claim 1 , wherein said article is a rubber article, a battery electrode, or a super capacitor. 
     
     
       8. The article of  claim 7 , wherein said rubber article is a belt, hose, tire, or vibration control component. 
     
     
       9. A method comprising:
 dispersing carbon nanostructures in a liquid medium to form a dispersion; 
 blending the dispersion with a particulate solid to form a blend; and 
 drying said blend to form a preblend; 
 wherein the preblend comprises a core-shell material comprising a core of particles of said particulate solid coated with a shell of said carbon nanostructures; 
 wherein the core particles comprise carbon-based particles selected from the group consisting of graphitic carbon and glassy carbon; and 
 wherein the carbon nanostructures consist of one or more from the group consisting of fullerenes, single-walled carbon nanotubes, multi-walled carbon nanotubes, and their chemical derivatives. 
 
     
     
       10. The method of  claim 9  further comprising adding the preblend to a polymer in a compounding process. 
     
     
       11. The method of  claim 9  further comprising using the preblend as part of a battery electrode or as part of an electrolyte medium in a super capacitor. 
     
     
       12. The method of  claim 9  further comprising using the preblend in an electrolyte medium, paint, coating, or slurry. 
     
     
       13. The method of  claim 9  wherein said liquid medium is an organic liquid. 
     
     
       14. The method of  claim 9  wherein said liquid medium comprises substituted aromatic molecules, alkyl substituted aromatics, halogenated substituted molecules, halogenated alkanes, partially hydrogenated aromatics, alkylamines, cyclic ethers, o-dichlorobenzene, xylene, benzene, dimethylformamide, ethylene chloride, chloroform, 1,2,4-trimethylbenzene, 1,2,3,4-tetramethylbenzene, tetrahydrofuran, 1,2-dibromobenzene, 1,1,2,2-tetrachloroethane, 1,2,3,4-tetrahydronaphthalene, octadecylamine, acetone and mixtures thereof. 
     
     
       15. The method of  claim 9  wherein said liquid medium is water or water stabilized by means of surfactant with such surfactant being at least one member selected from the group consisting of sodium cholate, sodium octylbenzene sulfonate, sodium butylbenzene sulfonate, sodium benzoate, sodium dodecyl sulfate, C 8 H 17 C 6 H 4 (OCH 2 CH 2 )n-OH wherein n is 10, dodecyltrimethylammonium bromide, dextrin, and polystyrene-polyethylene oxide diblock copolymer. 
     
     
       16. The preblend composition of  claim 2  wherein the shell coating on the core particles cover a surface area in the range of 50-100% of the total surface area of the core particles. 
     
     
       17. The preblend composition of  claim 2  wherein said preblend composition is further prepared by drying after said wet-mixing. 
     
     
       18. The preblend composition of  claim 2  wherein the preblend further comprises a nanotube network with carbon black particles dispersed therein. 
     
     
       19. A material composition comprising the preblend composition of  claim 2 , wherein said material composition is a polymer composition, an electrolyte medium, a paint, a coating, or a slurry. 
     
     
       20. An article comprising the preblend composition of  claim 2 , wherein said article is a rubber article, a battery electrode, or a super capacitor. 
     
     
       21. The article of  claim 20 , wherein said rubber article is a belt, hose, tire, or vibration control component.